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    题名 作者 年代 出处 被引量
1Welding Deviation Detection Algorithm Based on Extremum of Molten Pool Image Contour显示文摘The welding deviation detection is the basis of robotic tracking welding, but the on-line real-time measurement of welding deviation is still not well solved by the existing methods. There is plenty of information in the gas metal arc welding(GMAW) molten pool images that is very important for the control of welding seam tracking. The physical meaning for the curvature extremum of molten pool contour is revealed by researching the molten pool images, that is, the deviation information points of welding wire center and the molten tip center are the maxima and the local maxima of the contour curvature, and the horizontal welding deviation is the position difference of these two extremum points. A new method of weld deviation detection is presented, including the process of preprocessing molten pool images, extracting and segmenting the contours, obtaining the contour extremum points, and calculating the welding deviation, etc. Extracting the contours is the premise, segmenting the contour lines is the foundation, and obtaining the contour extremum points is the key. The contour images can be extracted with the method of discrete dyadic wavelet transform, which is divided into two sub contours including welding wire and molten tip separately. The curvature value of each point of the two sub contour lines is calculated based on the approximate curvature formula of multi-points for plane curve, and the two points of the curvature extremum are the characteristics needed for the welding deviation calculation. The results of the tests and analyses show that the maximum error of the obtained on-line welding deviation is 2 pixels(0.16 mm), and the algorithm is stable enough to meet the requirements of the pipeline in real-time control at a speed of less than 500 mm/min. The method can be applied to the on-line automatic welding deviation detection.ZOU Yong JIANG Lipei LI Yunhua XUE Long HUANG Junfen HUANG Jiqiang 2016Chinese Journal of Mechanical Engineering2016,29,1:12
2Heterogeneous oxidation of cyclohexanone catalyzed by TS-1:Combined experimental and DFT studies显示文摘Changjiu Xia Long Ju Yi Zhao Hongyi Xu Bin Zhu Feifei Gao Min Lin Zhenyu Dai Xiaodong Zou Xingtian Shu 2015催化学报2015,36,6:11
3Effects of yeast and yeast cell wall polysaccharides supplementation on beef cattle growth performance, rumen microbial populations and lipopolysaccharides production显示文摘This experiment was conducted to investigate the effects of live yeast and yeast cell wall polysaccharides on growth performance,rumen function and plasma lipopolysaccharides(LPS) content and immunity parameters of beef cattle.Forty Qinchuan cattle were randomly assigned to one of four treatments with 10 replicates in each treatment.The dietary treatments were: control diet(CTR),CTR supplemented with 1 g live yeast(2×10^10 live cell g^-1 per cattle per day(YST1),CTR supplemented with 2 g live yeast per cattle per day(YST2) and CTR supplemented with 20 g of yeast cell wall polysaccharides(30.0%≤β-glucan≤35.0%,and 28.0%≤mannanoligosaccharide≤32.0%) per cattle per day(YCW).The average daily gain was higher(P=0.023) and feed conversion ratio was lower(P=0.042) for the YST2 than the CTR.The digestibility of neutral detergent fiber(P=0.039) and acid detergent fiber(P=0.016) were higher in yeast supplemented groups.The acetic acid:propionic acid of the YST2 was lower compared with the CTR(P=0.033).Plasma LPS(P=0.032),acute phase protein haptoglobin(P=0.033),plasma amyloid A(P=0.015) and histamine(P=0.038) were lower in the YST2 compared with the CTR.The copies of fibrolytic microbial populations such as Fibrobacter succinogenes S85,Ruminococcus albus 7 and Ruminococcus flavefaciens FD-1 of the YST2 were higher(P<0.001),while the copies of typical lactate producing bacteria Streptococcus bovis JB1 was lower(P<0.001) compared with the CTR.Little differences were observed between the CTR,YST1 and YCW in growth performance,ruminal fermentation characteristics,microbial populations,immunity indices and total tract nutrient digestibility.It is concluded that the YST2 could promote fibrolytic microbial populations,decrease starch-utilizing bacteria,reduce LPS production in the rumen and LPS absorption into plasma and decrease inflammatory parameters,which can lead to an improvement in growth performance in beef cattle.PENG Quan-hui CHENG Long KANG Kun Tian Gang Mohammad Al-Mamun XUE Bai WANG Li-zhi ZOU Hua-wei Mathew Gitau Gicheha WANG Zhi-sheng 2020Journal of Integrative Agriculture2020,19,3:9
4Noninvasive Ultrasound Deep Brain Stimulation for the Treatment of Parkinson’s Disease Model Mouse显示文摘Modulating basal ganglia circuitry is of great signifcance in the improvement of motor function in Parkinson’s disease(PD).Here,for the frst time,we demonstrate that noninvasive ultrasound deep brain stimulation(UDBS)of the subthalamic nucleus(STN)or the globus pallidus(GP)improves motor behavior in a subacute mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP).Immunohistochemical c-Fos protein expression confrms that there is a relatively high level of c-Fos expression in the STN-UDBS and GP-UDBS group compared with sham group(both p<0.05).Furthermore,STN-UDBS or GPUDBS signifcantly increases the latency to fall in the rotarod test on day 9(p<0.05)and decreases the time spent climbing down a vertical rod in the pole test on day 12(p<0.05).Moreover,our results reveal that STN-UDBS or GP-UDBS protects the dopamine(DA)neurons from MPTP neurotoxicity by downregulating Bax(p<0.001),upregulating Bcl-2(p<0.01),blocking cytochrome c(Cyt C)release from mitochondria(p<0.05),and reducing cleaved-caspase 3 activity(p<0.01)in the ipsilateral substantia nigra(SN).Additionally,the safety of ultrasound stimulation is characterized by hematoxylin and eosin(HE)and Nissl staining;no hemorrhage or tissue damage is detected.Tese data demonstrate that UDBS enables modulation of STN or GP neural activity and leads to neuroprotection in PD mice,potentially serving as a noninvasive strategy for the clinical treatment of PD.Hui Zhou Lili Niu Long Meng Zhengrong Lin Junjie Zou Xiangxiang Xia Xiaowei Huang Wei Zhou Tianyuan Bian Hairong Zheng 2019Research2019,,1:9
5Continuous applications of biochar to rice: Effects on grain yield and yield attributes显示文摘Biochar is considered as a beneficial soil amendment for crop production. However, limited information is available on the effects of continuous applications of biochar on rice. In this study, a fixed field experiment was conducted in the early and late rice-growing seasons from 2015 to 2017. Grain yield and yield attributes with a widely-grown rice cultivar Zhongzao 39 were compared, with and without applications of biochar in each season. The results showed that grain yield initially decreased with biochar applications in the first three seasons due to decreases in grain weight and harvest index. Although there were further relative decreases in grain weight and harvest index for rice that was supplied with biochar in the fourth to sixth seasons, grain yield was increased(by 4–10%) because of increases in sink size(spikelets per m2) and total biomass. The increased sink size in rice whose soil had been supplied with biochar in the fourth to sixth seasons was achieved by increasing panicle size(spikelets per panicle) or number of panicles, or both. Our study suggests that the positive effects of biochar application on rice yield and yield attributes depend on the duration of biochar application. Further investigations are needed to determine what are the soil and physiological processes for producing yield responses associated with ongoing applications of biochar. Also, it should be evaluated the performance of biochar application combined with other management practices, especially those can increase the grain weight and harvest index in rice production.HUANG Min FAN Long JIANG Li-geng YANG Shu-ying ZOU Ying-bin Norman Uphoff 2019Journal of Integrative Agriculture2019,18,3:9
6Welding Polarity Effects on Weld Spatters and Bead Geometry of Hyperbaric Dry GMAW显示文摘Welding polarity has influence on welding stability to some extent, but the specific relationship between welding polarity and weld quality has not been found, especially under the hyperbaric environment. Based on a hyperbaric dry welding experiment system, gas metal arc welding(GMAW) experiments with direct current electrode positive(DCEP) and direct current electrode negative(DCEN) operations are carried out under the ambient pressures of 0.1 MPa, 0.4 MPa, 0.7 MPa and 1.0 MPa to find the influence rule of different welding polarities on welding spatters and weld bead geometry. The effects of welding polarities on the weld bead geometry such as the reinforcement, the weld width and the penetration are discussed. The experimental results show that the welding spatters gradually grow in quantity and size for GMAW with DCEP, while GMAW with DCEN can produce fewer spatters comparatively with the increase of the ambient pressure. Compared with DCEP, the welding current and arc voltage waveforms for DCEN is more stable and the distribution of welding current probability density for DCEN is more concentrated under the hyperbaric environment. When the ambient pressure is increased from 0.1 MPa to 1.0 MPa, the effects of welding polarities on the reinforcement, the weld width and the penetration are as follows: an increase of 0.8 mm for the weld reinforcement is produced by GMAW with DCEN and 1.3 mm by GMAW with DCEP, a decrease of 7.2 mm for the weld width is produced by DCEN and 6.1 mm by DCEP; and an increase of 3.9 mm for the penetration is produced by DCEN and 1.9 mm by DCEP. The proposed research indicates that the desirable stability in the welding procedure can be achieved by GMAW with DCEN operation under the hyperbaric environment.XUE Long WU Jinming HUANG Junfen HUANG Jiqiang ZOU Yong LIU Jian 2016Chinese Journal of Mechanical Engineering2016,29,2:9
7Constant Speed Control for Complex Cross-section Welding Using Robot Based on Angle Self-Test显示文摘Expandable profile liner(EPL) is a promising new oil well casing cementing technique, and welding is a major EPLs connection technology. Connection of EPL is still in the stage of manual welding so far, automatic welding technology is a hotspot of EPL which is one of the key technologies to be solved. A robot for automatic welding of '8' type EPL is studied. Four quadrants of mathematical equations of the 8-shaped cross-section track of EPL, consisting of multiple arcs, are established. Mechanism program for complex cross-section welding of EPL based on angle detection is proposed according to characteristics of small size, small valleys, and large forming errors, etc. A welding velocity vector control model is established by linkage control of a welding vehicle, a small driven actuator, and a height tracking mechanism. A constant speed control model based on an angle and symmetrical analysis model of rectangular coordinate system for EPL is built. Constraint conditions of constant speed control between each section are analyzed with 4 sections in first quadrant as an example, and cooperation work mechanism of the welding vehicle and the small tracking actuator is established based on pressure detection. The constant speed control model using angle self-test can be used to avoid the need for a precise mathematical model for tracking control and to adapt manufacture and installation deviation of EPL workpiece. The model is able to solve constant speed and trajectory tracking problems of EPL cross-section welding. EPL seams welded by the studied robot are good in appearance, and non-destructive testing(NDT) shows the seams are good in quality with no welding defects. Bulge tests show that the maximum pressure of welded EPL is 35 MPa, which can fulfill expansion performance requirements.XUE Long ZOU Yong HUANG Jiqiang HUANG Junfen TAO Xinghua HU Yanfeng 2014Chinese Journal of Mechanical Engineering2014,27,2:8
8Prospective randomized comparison of transumbilical two-port laparoscopic and conventional laparoscopic varicocele ligation显示文摘我们证实了一个新奇方法为精索静脉曲张把 transumbilical 称为二港口的 laparoscopic 精索静脉曲张结扎(TTLVL ) ,它仍然被需要评估。在这研究,有等级 II-III 的左自发的征兆的精索静脉曲张的 90 个病人随机根据分级系统的 Dubin 被分到 TTLVL (n = 45 ) 并且常规 laparoscopic 精索静脉曲张结扎(CLVL )(n = 45 ) 。人口统计, intraoperative,手术后,并且后续数据在二个组之间被记录并且比较。在二个组的所有过程没有 intraoperative 复杂并发症和没有变换成功地被完成打开外科。没有重要差别在起作用的时间被发现,恢复在二个组之间的阴囊的疼痛的移动,肠恢复,手术后的医院停留,和手术后的分辨率(P >0.05 ) 。然而,为 TTLVL 组的手术后的吝啬的视觉模拟疼痛规模分数都与 CLVL 相比手术后地是在 24 h, 48 h, 72 h,和 7 天的更少(P = 0.001, 0.010, 0.006,和 0.027,分别地) 。在手术后的月内的吝啬的耐心的疤评价问询表分数 3 为 CLVL 组与 32.1 相比为 TTLVL 组是 29.7 (P <0.001 ) 。没有阴囊的萎缩,在后续时期期间在两个组观察。学习证明 TTLVL 是为精索静脉曲张的治疗的 CLVL 的一种安全、可行、有效的最低限度地侵略的外科的选择。与 CLVL 相比, TTLVL 可以减少手术后伤害并且改善化妆结果。Guo-Xi Zhang Jan Yang Da-Zhi Long Min Liu Xiao-Feng Zou Yuan-Hu Yuan Ri-Hai Xiao Yi-Jun Xue Xin Zhong Quan-Liang Liu Fo-Lin Liu Bo Jiang Rui-Quan Xu Kun-Lin Xie 2017Asian Journal of Andrology2017,19,1:8
9Influence of weight management on the prognosis of steatohepatitis in chronic hepatitis B patients during antiviral treatment显示文摘Background:Although concomitant nonalcoholic steatohepatitis(NASH)is common in chronic hepatitis B(CHB),the impact of viral factors on NASH and the outcome of CHB patients concomitant with NASH remain unclear.We aimed to investigate the outcomes of NASH in CHB patients receiving antiviral treatment.Methods:In the post-hoc analysis of a multicenter trial,na?ve CHB patients receiving 72-week entecavir treatment were enrolled.We evaluated the biochemical,viral and histopathological responses of these patients.The histopathological features of NASH were also evaluated,using paired liver biopsies at baseline and week 72.Results:A total of 1000 CHB patients were finally enrolled for analysis,with 18.2%of whom fulfilling the criteria of NASH.A total of 727 patients completed entecavir antiviral treatment and received the second biopsy.Serum HBe Ag loss,HBe Ag seroconversion and HBV-DNA undetectable rates were similar between patients with or without NASH(P>0.05).Among patients with NASH,the hepatic steatosis,ballooning,lobular inflammation scores and fibrosis stages all improved during follow-up(all P<0.001),46%(63/136)achieved NASH resolution.Patients with baseline body mass index(BMI)≥23 kg/m2(Asian criteria)[odds ratio(OR):0.414;95%confidence interval(95%CI):0.190-0.899;P=0.012]and weight gain(OR:0.187;95%CI:0.050-0.693;P=0.026)were less likely to have NASH resolution.Among patients without NASH at baseline,22(3.7%)developed NASH.Baseline BMI≥23 kg/m2(OR:12.506;95%CI:2.813-55.606;P=0.001)and weight gain(OR:5.126;95%CI:1.674-15.694;P=0.005)were predictors of incident NASH.Conclusions:Lower BMI and weight reduction but not virologic factors determine NASH resolution in CHB.The value of weight management in CHB patients during antiviral treatment deserves further evaluation.Xiu-Juan Chang Yi-Wen Shi Jing Wang Hua-Bao Liu Yan Chen Xiao-Ning Zhu Yong-Ping Chen Zu-Jiang Yu Qing-Hua Shang Lin Tan Qin Li Li Jiang Guang-Ming Xiao Liang Chen Wei Lu Xiao-Yu Hu Qing-Hua Long Lin-Jing An Zi-Yuan Zou Vincent Wai-Sun Wong Yong-Ping Yang Jian-Gao Fan 2021Hepatobiliary & Pancreatic Diseases International2021,20,5:8
10Molecular phylogeography and evolutionary history of Picea likiangensis in the Qinghai-Tibetan Plateau inferred from mitochondrial and chloroplast DNA sequence variation显示文摘Jia-Bin ZOU Xiao-Li PENG Long LI Jian-Quan LIU Georg MIEHE Lars OPGENOORTH 2012Journal of Systematics and Evolution2012,50,4:7
11Chemical Composition and Antimicrobial Activity of Essential Oil of Asarum caulescene显示文摘Both essential oils of fresh and air-dried Asarum caulescene (Maxim.) were analyzed by GC-MS in three different polarities. The results show that thirty-four components were identified in the oils, and main compounds of both oils were β-pinene (7.63% vs. 20.72%), 2-carene (8.94% vs. 7.99%), β-phellandrene (7.80% vs. 14.39%), 1,8-cineole (8.91% vs. 13.29%) and germacrone (46.64% vs. 6.64% ), however, the content of monoterpene hydrocarbons(30.29% vs. 52.30% ) and oxygenated sesquiterpenes( 47.69% vs. 10.65%) of both oils was different. The antimicrobial activity of the oil was evaluated against 3 fungi and 11 bacteria including 7 clinical isolated strains. Our results showed that both oils presented a broad antimicrobial spectrum, and compared with the essential oil from fresh herb, the extracted oil from dried herb had better antimicrobial activity, its minimum inhibitory concentration(c_ mi ) values of dried herb were 0.16-2.5 g/L and lowest minimum bactericidal concentration(c_ mb ) value was 0.31 g/L.ZHU Shunying YANG Yang YU Huaidong YING Yue LONG Dong Zou Guolin 2006Wuhan University Journal of Natural Sciences2006,11,3:7
12Preparation and Characterization of Microencapsulated Hexadecane Used for Thermal Energy Storage显示文摘Polyurea microcapsules about 2.5μm in diameter containing phase change material for thermal energy storage application were synthesized and characterized by interfacial polycondensation method with toluene-2,4-diisocyanate and ethylenediamine as monomers in an emulsion system. Hexadecane was used as a phase change material and OP, which is nonionic surfactant, and used as an emulsifier. The chemical structure and thermal behavior of the microcapsules were investigated by FTIR and thermal analysis respectively. The results show encapsulated hexadecane has a good potential as a solar energy storage material.Guang Long ZOU Zhi Cheng TAN Xiao Zheng LAN Li Xian SUN Tao ZHANG 2004Chinese Chemical Letters2004,15,6:7
13Physicochemical Control of the Early Permian Xiangshan Fe-Ti Oxide Deposit in Eastern Tianshan(Xinjiang),NW China显示文摘The Xiangshan mafic-ultramafic complex is one of the major Early Permian mafic-ultramafic intrusions in eastern Tianshan(Xinjiang, NW China), and consists of two major intrusive phases. The first intrusive phase is mainly gabbroic rocks hosting ilmenite mineralization, while the second intrusive phase is mainly lherzoilite associated with Ni-Cu sulfide mineralization. The Xiangshan ilmenite orebodies hosted in the Fe-Ti oxide-bearing gabbro occur along the contact between hornblende gabbros and leucogabbros. The hornblende gabbros and Fe-Ti oxide rich gabbros at Xiangshan are newly dated to be Early Permian(280.1 and 279.2 Ma, respectively). Major and trace element compositions of zircons and whole rocks from Xiangshan hornblende gabbro and Fe-Ti oxide gabbro have been measured by in situ excimer laser ablation ICP-MS. Zircon Ce^(4+)/Ce^(3+) ratios based on lattice-strain model and Ti-in-zircon temperatures of hornblende gabbro and Fe-Ti oxide gabbro of the Xiangshan complex are calculated to evaluate the physicochemical variations during the ilmenite mineralization. Whole-rock geochemistry and zircon trace element geochemistry suggest that Fe-Ti oxide gabbros were formed from a basaltic parent magma which had undergone a transfromation from being H_2O-rich to H_2O-poor. During the magmatic evolution, primitive, H_2O-poor basaltic melts may have been replenished into the system, increasing its solidus temperature and decreasing its oxygen fugacity and H_2O contents. This may have supperessed the Ti-rich poikilitic hornblende fractionation and promoted the plagioclase fractionation, which consequently concentrated the ore-forming components in the residual melts and generated the ilmenite mineralization.Yu Shi Yuwang Wang Jingbin Wang Lutong Zhao Hongjing Xie Lingli Long Tao Zou Dedong Li Guochao Zhou 2018Journal of Earth Science2018,29,3:6
14Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure显示文摘By using high-pressure treatment, two mutant lines were obtained from a genetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together with the original line (Bijing38), was either undigested or digested by Hpa II/Msp I, and then subjected to molecular analy-sis using two markers, ISSR and RAPD. Results indicated that changes in the PCR amplification pro-files of both markers are apparent in the two mutant lines compared with the original rice cultivar, suggesting that there had been both sequence changes and DNA methylation modifications in the mutant lines. Southern blot analysis using diverse sequences, including two cellular genes (S2 and S3), a set of retrotransposons (Osr7, Osr36, Tos19 and more), and a MITE transposon family (mPing and Pong), confirmed the results, and indicated that changes in DNA methylation pattern, genomic structure, and possible activation of some transposons indeed occurred in the mutant lines. Moreover, these changes are stably maintained through selfed generations and in different organs. Thus, our results indicate that it is possible to obtain stable mutants in rice by high pressure treatments, and the molecular basis of the mutants may include both genetic and epigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plant mutagenesis.SHEN Sile1,3, WANG Zhenwei3, SHAN Xiaohui2, WANG Hua3, LI Ling3, LIN Xuyun2, LONG Likun2, WENG Kenan4, LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin University, Changchun 130012, China 2. Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China 3. College of Life Science, Jilin University, Changchun 130012, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2006Science China(Life Sciences)2006,49,2:6
15Modulation characteristics and microwave generation for AlGaInAs/InP microring lasers under four-wave mixing显示文摘The dynamic characteristics are investigated for a microring laser with an external radius of 12μm subject to external optical injection.Single-mode operation with a side mode suppression ratio of 33.4 dB is realized at a biasing current of 25 mA and a temperature of 290 K,and the corresponding small-signal modulation response is obtained with a resonance peak frequency of 7.5 GHz.Under the optical injection from a tunable laser,the improvements of the small-signal modulation response induced by four-wave mixing are observed for the microring laser,which shows an additional resonance peak around the frequency of the beat frequency between the lasing mode and the injecting light.Furthermore,optical generation of a microwave signal is realized by the light beating between the lasing mode and the injecting light measured by a high-speed photodetector and a spectrum analyzer.Ling-Xiu Zou Yong-Zhen Huang Xiao-Meng Lv Bo-Wen Liu Heng Long Yue-De Yang Jin-Long Xiao Yun Du 2014Photonics Research2014,2,6:6
16Aggregate stability and associated C and N in a silty loam soil as affected by organic material inputs显示文摘To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw(CS), biogas residue(BR), mushroom residue(MR), wine residue(WR), pig manure(PM), with a mineral fertilizer(CF) and a no-fertilizer(CK) treatment as a control. Our objectives were: i) to quantify the effects of organic materials on soil C and N accumulation; ii) to evaluate the effects of organic materials on soil aggregate stability, along with the total organic carbon(TOC), and N in different aggregate fractions; and iii) to assess the relationships among the organic material components, soil C and N, and C, N in aggregate fractions. The trial was conducted in Wuqiao County, Hebei Province, China. The organic materials were incorporated at an equal rate of C, and combined with a mineral fertilizer in amounts of 150 kg N ha-1, 26 kg P ha-1 and 124 kg K ha-1 respectively during each crop season of a wheat-maize rotation system. The inputted C quantity of each organic material treatment was equivalent to the total amount of C contained in the crop straw harvested in CS treatement in the previous season. TOC, N, water-stable aggregates, and aggregate-associated TOC and N were investigated. The results showed that organic material incorporation increased soil aggregation and stabilization. On average, the soil macroaggregate proportion increased by 14%, the microaggregate proportion increased by 3%, and mean-weight diameter(MWD) increased by 20%. TOC content followed the order of PM>WR>MR>BR>CS>CK>CF; N content followed the order WR>PM>MR>BR>CS>CF>CK. No significant correlation was found between TOC, N, and the quality of organic material. Soil silt and clay particles contained the largest part of TOC, whereas the small macroaggregate fraction was the most sensitive to organic materials. Our results indicate that PM and WR exerted better effects on soil C and N accumulation, followed by MR and BR, suggesting that organic materials from ex situ farmland could promote soil quality more as compared to straw returned in situ.LONG Pan SUI Peng GAO Wang-sheng WANG Bin-bin HUANG Jian-xiong YAN Peng ZOU Juan-xiu YAN Ling-ling CHEN Yuan-quan 2015Journal of Integrative Agriculture2015,14,4:6
17Numerical analysis of dislocations of the face slabs of the Zipingpu Concrete Faced Rockfill Dam during the Wenchuan earthquake显示文摘The Zipingpu Concrete Faced Rockfill Dam (CFRD) was obviously damaged during the Wenchuan earthquake in 2008. A wide range of dislocations occurred along the horizontal construction joints at EL. 845m, between the face slabs constructed in the second and third stages. The maximum displacement of the dislocations reached 17cm. In this study, the slab dislocations were investigated using finite element (FE) analysis. The method based on strain potential was applied to compute the permanent deformation of the Zipingpu Dam during the Wenchuan earthquake. The calculated magnitude of the slab dislocation showed good agreements with the field measurements. The dislocation mechanism was discussed. The results show that the dislocation of the concrete slab is a subsequent damage after the permanent deformation of the rockfill materials. The effects of the shear strength and the direction of the construction joints, the reservoir water level and the seismic waves were studied. The shear strength and the direction of the construction joints, reservoir water level and have a significant effect on the dislocation displacement. The dislocation can be effectively reduced by measures such as changing the direction of the construction joints or improving the shear strength at the horizontal joints.Kong Xianjing Zhou Yang Zou Degao Xu Bin Yu Long 2011Earthquake Engineering and Engineering Vibration2011,10,4:6
18Toward emerging gallium oxide semiconductors:A roadmap显示文摘Owing to the advantages of ultra-wide bandgap and rich material systems,gallium oxide(Ga_(2)O_(3))has emerged as a highly viable semiconductor material for new researches.This article mainly focuses on the growth processes,material characteristics,and applications of Ga_(2)O_(3).Compared with single crystals and the epitaxial growth of other wide-bandgap semiconductors,large-size and high-quality��-Ga_(2)O_(3) single crystals can be efficiently grown with a low cost,making them highly competitive.Thanks to the availability of high-quality single crystals,epi-taxial films,and rich material systems,high-performance semiconductor devices based on Ga_(2)O_(3) go through a booming development in recent years.The defects and interfaces of Ga_(2)O_(3) are comprehensively analyzed owing to their significant influence on practical applications.In this study,the two most common applications of Ga_(2)O_(3) materials are introduced.The high breakdown electric field,high working temperature,and excellent Baliga’s figure-of-merit of Ga_(2)O_(3) represent an inspiring prospect for power electronic devices.In addition,the excellent absorption in deep-ultraviolet band provides new ideas for optoelectronic detectors and ensures the dramatic progress.Finally,the summary,challenges,and prospects of the Ga_(2)O_(3) materials and devices are presented and discussed.Yuan Yuan Weibing Hao Wenxiang Mu Zhengpeng Wang Xuanhu Chen Qi Liu Guangwei Xu Chenlu Wang Hong Zhou Yanni Zou Xiaolong Zhao Zhitai Jia Jiandong Ye Jincheng Zhang Shibing Long Xutang Tao Rong Zhang Yue Hao 2021Fundamental Research2021,1,6:5
19High performance white LED driver with single-wire serial-pulse digital dimming显示文摘A high performance white light emitter diode (LED) driver based on boost converter with novel single-wire serial-pulse digital dimming (SWSP) is proposed. The driver uses external serial programmed pulses and internal clock to simplify brightness control. By embedding a 5-bit digital analog converter (DAC) into the driver, wide dimming range is achieved. Moreover, a new dynamic slope compensation circuit is presented and other key circuits of the driver are optimized to get higher efficiency and fast transition response. A practical circuit is implemented with 0.6 um bipolar complementary-metal-oxide-semiconductor double-diffused-metal-oxide-semiconductor (BCD) technology. The simulation results show that the driver can provide both wide output current from 1.3 mA to 42 mA with 32-level digital dimming and higher efficiency up to 83% while it works at 1 MHz switching frequency with the input voltage variation from 2.7 V to 5.5 V.YU Kai ZOU Xue-cheng LONG Shuang WANG Wei-xu 2009The Journal of China Universities of Posts and Telecommunications2009,16,1:5
20The RNA-binding protein Musashi2 governs osteoblast-adipocyte lineage commitment by suppressing PPARγsignaling显示文摘Osteoporosis caused by aging is characterized by reduced bone mass and accumulated adipocytes in the bone marrow cavity. How the balance between osteoblastogenesis and adipogenesis from bone marrow mesenchymal stem cells(BMSCs) is lost upon aging is still unclear. Here, we found that the RNA-binding protein Musashi2(Msi2) regulates BMSC lineage commitment. Msi2 is commonly enriched in stem cells and tumor cells. We found that its expression was downregulated during adipogenic differentiation and upregulated during osteogenic differentiation of BMSCs. Msi2 knockout mice exhibited decreased bone mass with substantial accumulation of marrow adipocytes, similar to aging-induced osteoporosis. Depletion of Msi2 in BMSCs led to increased adipocyte commitment. Transcriptional profiling analysis revealed that Msi2 deficiency led to increased PPARγ signaling.RNA-interacting protein immunoprecipitation assays demonstrated that Msi2 could inhibit the translation of the key adipogenic factor Cebpα, thereby inhibiting PPAR signaling. Furthermore, the expression of Msi2 decreased significantly during the aging process of mice, indicating that decreased Msi2 function during aging contributes to abnormal accumulation of adipocytes in bone marrow and osteoporosis. Thus, our results provide a putative biochemical mechanism for aging-related osteoporosis, suggesting that modulating Msi2 function may benefit the treatment of bone aging.Jinlong Suo Sihai Zou Jinghui Wang Yujiao Han Lingli Zhang Chenchen Lv Bo Jiang Qian Ren Long Chen Lele Yang Ping Ji Xianyou Zheng Ping Hu Weiguo Zou 2022Bone Research2022,10,3:5
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