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M_2(pbtcH)(phen)_2(H_2O)_2[M(Ⅱ)=Co,Ni]:Mixed-ligated metal phosphonates based on 5-phosphonatophenyl-1,2,4-tricarboxylic acid showing double chain structures

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Chinese Chemical Letters 2014年第6期25卷 835-838页

作者： Tao zheng Min Ren Song-Song bao Li-Min zheng State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

Two new mixed-ligated metal phosphonates, M2（pbtcH）（phen）2（H2O）2 [M（Ⅱ）=Co （1）, Ni （2）] （pbtcH5 = 5-phosphonatophenyl-1,2,4-tricarboxylic acid, phen = 1,10-phenanthroline）, have been syn- thesized and characterized. Both show one-dimensional double chain structures, where the M（phen）（H2O） moieties are chelated and bridged by pbtcH4 through the carboxylate and phosphonate oxygen atoms. The chains are connected by hydrogen bonding interactions and π-π stacking, forming a three-dimensional supramolecular structure. The IR and magnetic properties of the two compounds are also investigated.

关键词： 5-Phosphonatophenyl- 1,2,4-tricarboxylic acid Cobalt Nickel Magnetic property

Ground moving target detection and location based on SAR images for distributed spaceborne SAR

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Science in China(Series F) 2005年第5期48卷 632-646页

作者： LI Zhenfang bao zheng YANG Fengfeng Key Laboratory for Radar Signal Processing Xidian University Xran 710071 China National University of Defence Technology Changsha 4100731 China

This paper investigates data processing approaches to detect and locate ground moving targets using distributed spaceborne SAR systems with long cross-track baselines. In particular, it investigates the performance of ground moving target detection for two typical satellite formations： Cartwheel and Pendulum. An approach based on SAR images and a space-time adaptive processing （STAP） algorithm is proposed in order to overcome the effects of the ground terrain on the clutter suppression. The key idea of the approach is firstly to reduce the clutter degrees of freedom greatly by using conventional SAR imaging processing. Then the ground terrain clutter within each SAR pixel can be effectively cancelled by using the very limited spatial degrees of freedom. Finally, constant-false-alarm-rate （CFAR） techniques can be used to detect the remaining target SAR pixels after clutter cancellation. An approach to relocate the detected targets is also proposed, which is based on the estimation of the Doppler spectrum shifts of ground moving targets relative to the clutter Doppler spectrum. The proposed approaches in this paper have the advantages of simplicity and high efficiency.

关键词： formation-flying satellites ground moving target indication spaceborne synthetic apertureradar (spaceborne SAR) space-time adaptive processing (STAP) cartwheel pendulum.

Parallel processing architecture of H.264 adaptive deblocking filters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1160-1168页

作者： Hu WEI Tao LIN zheng-hui LIN Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

In H.264,computational complexity and memory access of deblocking filters are variable,dependent on video *** paper proposes a VLSI architecture of deblocking filters with adaptive dynamic power,which avoids redundant computations and memory accesses by precluding the blocks that can be *** vertical and horizontal edges are simulta-neously processed in an advanced scan order to speed up the *** a result,dynamic power of the proposed architecture can be reduced adaptively(up to about 89%) for different videos,and the off-chip memory access is improved when compared to previous ***,the processing capability of the proposed architecture is in particular appropriate for real-time deblocking of high-definition television(HDTV,1920×1080 pixels/frame,60 frames/s video signals) video operation at 62 *** the proposed architecture,power can be reduced by up to about 89% and processing time by from 25% to 81% compared with previous designs.

关键词： Deblocking filter Adaptive dynamic power Parallel processing Pipeline H.264

A p53/CPEB2 negative feedback loop regulates renal cancer cell proliferation and migration

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Journal of Genetics and Genomics 2021年第7期48卷 606-617页

作者： Jiehui Di Guang Zhao hui Wang Yaoyao Wu Zhongjun Zhao bao Zhu Yanping Zhang Junnian zheng Yong Liu Ying Hu School of Life Science and Technology Harbin Institute of TechnologyHarbinHeilongjiang 150001China Cancer Institute Xuzhou Medical UniversityXuzhouJiangsu 221002China Center of Clinical Oncology Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu 221002China Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy Cancer InstituteXuzhou Medical UniversityXuzhouJiangsu 221002China Department of Radiation and Lineberger Comprehensive Cancer Center The University of North Carolina at Chapel Hill450 West DriveChapel HillNC 27599-7461USA Shenzhen Graduate School of Harbin Institute of Technology Shenzhen 518055China

The tumor suppressor p53 transactivates the expression of multiple genes to exert its multifaceted functions and ultimately maintains genome ***,cancer cells develop various mechanisms to diminish p53 expression and bypass the cell cycle *** this study,we identified the gene encoding RNAbinding protein cytoplasmic polyadenylation element-binding protein 2(CPEB2)as a p53 *** turn,CPEB2 decreases p53 messenger RNA stability and translation to fine-tune p53 ***,we showed that CPEB2 binds the cytoplasmic polyadenylation elements in the p5330-untranslated region,and the RNA recognition motif and zinc finger(ZF)domains of CPEB2 are required for this ***,we found that CPEB2 was upregulated in renal cancer tissues and promotes the renal cancer cell proliferation and *** oncogenic effect of CPEB2 is partially dependent on negative feedback regulation of ***,we identify a novel regulatory feedback loop between p53 and CPEB2 and demonstrate that CPEB2 promotes tumor progression by inactivating p53,suggesting that CPEB2 is a potential therapeutic target in human renal cancer.

关键词： p53 CPEB2 Cell proliferation Migration Renal cancer

Changes in the depths of seasonal freezing and thawing and their effects on vegetation in the Three-River Headwater Region of the Tibetan Plateau

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Journal of Mountain Science 2019年第12期16卷 2810-2827页

作者： WANG Rui DONG Zhi-bao ZHOU zheng-chao School of Geography and Tourism Shaanxi Normal University

Frozen ground degradation plays an important role in vegetation growth and activity in high-altitude cold *** study estimated the spatiotemporal variations in the active layer thickness(ALT)of the permafrost region and the soil freeze depth(SFD)in the seasonally frozen ground region across the Three Rivers Source Region(TRSR)from 1980 to 2014 using the Stefan equation,and differentiated the effects of these variations on alpine vegetation in these two *** results showed that the average ALT from 1980 to 2014 increased by23.01 cm/10 a,while the average SFD decreased by 3.41 cm/10 a,and both changed intensively in the transitional zone between the seasonally frozen ground and *** 1982-2014,the increase in the normalized difference vegetation index(NDVI)and the advancement of the start of the vegetation growing season(SOS)in the seasonally frozen ground region(0.0078/10 a,1.83 d/10 a)were greater than those in the permafrost region(0.0057/10 a,0.39 d/10 a).The results of the correlation analysis indicated that increases in the ALT and decreases in the SFD in the TRSR could lead to increases in the NDVI and advancement of the *** soil moisture played a critical role in vegetation growth in association with the increasing ALT and decreasing *** NDVI for all vegetation types in the TRSR except for alpine vegetation showed an increasing trend that was significantly related to the SFD and *** the study period,the general frozen ground conditions were favorable to vegetation growth,while the average contributions of ALT and SFD to the interannual variation in the NDVI were greater than that of precipitation but less than that of temperature.

关键词： Frozen soil depth Active layer thickness Alpine vegetation Climate warming Three Rivers Source Region

Young thoracic vertebra diffuse idiopathic skeletal hyperostosis with Scheuermann disease:A case report

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World Journal of Clinical Cases 2023年第3期11卷 655-661页

作者： Wen-zheng Liu zheng-Qi Chang Zhe-Ming bao The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinan 250000Shandong ProvinceChina Department of Orthopedics 960th Hospital of PLAJinan 250031Shandong ProvinceChina

BACKGROUND Diffuse idiopathic skeletal hyperostosis(DISH)is a disorder characterised by the calcification and ossification of ligaments and *** is a frequent occurrence in elderly males,but rarely encountered in younger *** SUMMARY A 24-year-old male was admitted to the hospital due to low back pain accompanied with numbness in both lower limbs for 10 *** clinical examination and imaging tests,the patient was diagnosed with DISH with Scheuermann disease and thoracic spinal *** the operation and medical treatment,the patient had hypoesthesia of the skin below the xiphoid ***,a standard laminectomy was conducted using ultrasonic bone curette and internal fixation was ***,the patient was given corticosteroids,neurotrophic drugs,hyperbaric oxygen and electric *** a result of the treatment,the patient’s sensory level decreased to the navel level and there was no major change in the muscle strength of the lower *** follow-up,the patient’s skin sensation has returned to *** This case is a rare instance of DISH co-existing with Scheuermann’s disease in a young *** provides a valuable reference point for spine surgeons,as DISH is more commonly observed in middle-aged and elder adults.

关键词： Diffuse idiopathic skeletal hyperostosis Scheuermann disease Thoracic spinal stenosis Case report

Repassivation behavior of alloy 690TT in simulated primary water at different temperatures

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Journal of Materials Science & Technology 2021年第9期68卷 227-235页

作者： Ji Liu Jianqiu Wang Zhiming Zhang hui zheng Key Laboratory of Nuclear Materials and Safety Assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear MaterialsInstitute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China State Nuclear Power Plant Service Company Shanghai200233China

The repassivation behavior of Alloy 690 T T in simulated primary water at different temperatures was investigated by the rapid scratching electrode technique together with electrochemical *** results showed that the repassivation process had three stages: the initial stage conformed to the place exchange model, the final stage conformed to the high field ion conduction model and in between there was a transition stage. At the initial stage, when the repassivation process of alloys was controlled by the place exchange model, anodic dissolution of substrate was dominated;after the film coverage rate was more than 0.99, the repassivation process of alloys was controlled by high field ion conduction model. Increasing the temperature resulted in a reduction of the repassivation rate and protectiveness of the passive film. The correlations among several mechanisms describing the repassivation behavior of alloys were discussed.

关键词： Repassivation Electrochemistry High temperature corrosion Alloy 690TT Electrochemical impedance spectroscopy

Luminosity Function of the Cluster of Galaxies Abell 566

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 620-628页

作者： Quan-bao Xiao zheng-Yi Shao Xu Zhou Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Joint Institute for Galaxy ＆ Cosmology Chinese Academy of Sciences Shanghai 200030 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We investigate the Luminosity Function （LF） of the cluster of galaxies Abell 566. The photometric data of 15 intermediate-bands are obtained from the Beijing-Arizona- Taiwan-Connecticut （BATC） photometric sky survey. For each of the 15 wavebands, the LF of cluster galaxies is well modelled by the Schechter function, with characteristic luminosities from -18.0 to -21.9 magnitude, from the α- to the p-band. Morphological dependence of the LF is investigated by separating the cluster members into ＇red＇ and ＇blue＇ subsamples. It is clear that late type galaxies have a steeper shape of LF than the early type galaxies. We also divided the sample galaxies by their local environment. It was found that galaxies in the sparser region have steeper shape of LF than galaxies in the denser region. Combining the results of morphological and environmental dependence of LFs, we show that Abell 566 is a well relaxed cluster with positive evidence of galaxy interaction and merger, and excess number of bright early type galaxies located in its denser region.

关键词： galaxy cluster individual Abell 566 -- galaxy photometry -- galaxy lumi- nosity function

Size effects on process performance and product quality in progressive microforming of shafted gears revealed by experiment and numerical modeling

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Advances in Manufacturing 2023年第1期11卷 1-20页

作者： Jun-Yuan zheng hui Liu Ming-Wang Fu Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China

As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production *** is a manufacturing process to produce microgears to meet the *** to the small geometrical size,there are uncertain process performance and product quality issues in this production *** this study,the shafted microgears were fabricated in two different scaling factors with four grain sizes using a progressively extrusion-blanking *** explore the unknown of the process,grain-based modeling was proposed and employed to simulate the entire forming *** results show that when the grains are large,the anisotropy of single grains has an obvious size effect on the forming behavior and process performance;and the produced geometries and surface quality are worsened;and the deformation load is *** deformation zones were identified in the microstructures with different hardness and distributions of stress and *** simulation by using the proposed model successfully predicted the formation of zones and revealed the inhomogeneous deformation in the forming *** undesirable geometries of microgears including material unfilling,burr and inclination were observed on the shaft and teeth of gear,and the inclination size is increased obviously with grain *** avoid the formation of inclination and material unfilling,the punch was redesigned,and a die insert was added to constraint the bottom surface of the gear *** new products had then the better forming quality.

关键词： Microforming Microprocess performance Microforming quality Size effect affected deformation behavior Die design optimization